21 terms

Physical/Chemical Change in Digestion

physical change
when a substance changes its size, shape, or state. No new substance is formed
chemical change
occurs when a new substance is formed as the result of a chemical reaction
chemical reaction
occurs anytime a chemical bond is broken or added
the process by which the body breaks down food into small nutrient molecules
digestive system
collection of organs used to break down foods into energy and building material for the body
mechanical digestion
Part of digestion that uses movement and muscles to break down food
chemical digestion
occurs when enzymes and other chemicals break down large food molecules into smaller ones
part of the body where both chemical and mechanical digestion begins
liquid secreted into the mouth that contains mucus and digestive enzymes that start chemical digestion
storage form of glucose in plants
enzyme in saliva that breaks the chemical bonds in starches
tube in which food travels from mouth to the stomach
large muscular sac that continues the mechanical and chemical digestion of food
measure of how acidic or basic a solution is; the scale ranges from below 0 to above 14; solution with pH above 7 is basic and a pH below 7 is acidic
litmus paper
an indicator paper that turns red in an acid and blue in a base
a substance that can soak up H⁺ ions, thus reducing acidity
also called alkaline/basic. Has a pH above 7
any compound that forms H+ ions in solution. Has a pH below 7
stomach acid
solution with a pH of 1.5 to 2.0. It kills bacteria and helps digest your food
small intestine
responsible for most chemical digestion and absorption of nutrients
Fingerlike projections in the small intestine that increase surface area and maximize the absorption of nutrients.
large intestine
the last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body